Geographic Range

Solitary sandpipers (Tringa solitaria) encompass two subspecies, Tringa solitaria solitaria and Tringa solitaria cinnamomea. They are migratory shorebirds found across much of North America with a broad breeding range spanning from Labrador, in Canada to Alaska, in the United States. Tringa solitaria solitaria, the easternmost representative, breeds as far southeast as the Yukon Territory, Canada and migrates throughout the United States, largely east of the Rocky Mountains, and through the West Indies and Central America, to southern South America. Tringa solitaria cinnamomea, the western representative, breeds further north, from northeast Manitoba, further northwest to western Alaska. T. solitaria cinnamomea migrates throughout the United States as well, largely west of the Mississippi River into Central America through to Bolivia, Paraguay, and south-central Argentina. (Conover, 1944; Eldridge, 1992; Leukering, 2010)

Habitat

Solitary sandpipers are found most commonly along the banks of small, quiet, wooded freshwater bodies of water. During migration, these birds are found along the shores of wooded streams, in narrow marsh channels and along open mudflats. They are also sometimes found in places not usually frequented by other shorebirds including drainage ditches and mud puddles. Solitary sandpipers typically are found avoiding salt water, including tidal flats and salt marshes, and therefore are a largely freshwater species. During breeding season, solitary sandpipers nest amongst woodland pools in nests created by other birds. Solitary sandpipers breed in boreal forests, such as those of Canada and Alaska, and winter in the tropics, in swamps and along riverbanks. (Conover, 1944; Leukering, 2010; Moskoff, 2011; Oring, 1973)

Physical Description

The two solitary sandpiper subspecies appear very similar; however, they have many distinguishing characteristics. Juveniles of the subspecies are easier to distinguish than adults, though the downy plumage between both subspecies appears identical. Adults are medium-sized with greenish legs, a moderately-sized neck and a straight, thin bill. In flight, their wings are dark on the underside, contrasting with their white belly. A white eye ring is present in both subspecies. Solitary sandpipers average approximately 19 to 23cm in length and between 31 to 65g in weight, with an average weight of 48.4g. Females are overall larger in length and weight than males. (Conover, 1944; Leukering, 2010; Moskoff, 2011)

Juvenile eastern solitary sandpipers (Tringa solitaria solitaria) have a dark brown dorsal surface that is notably less olive than that of western solitary sandpipers (Tringa solitaria cinnamomea) with white or grayish-white spotting on their upper bodies. The lower throat of these birds is typically a dusky wash of color. Most juveniles have immaculate outer primary feathers, free of mottling. Wingspans of female juveniles tend to be larger than that of males. The breeding plumage of adult eastern solitary sandpipers consists of generally spotless outer wing feathers, though some mottling can be observed in a small portion of the population on the inner web of their outermost primary feather. Their upperparts and loral feathers are dusky blackish in color with a darker outermost primary (p10) shaft and p10 inner web. This eastern variety is smaller than the western variety, with male wing lengths of 123 to 132.5mm, with an average of 127.5mm, and females wing lengths of 127 to 140mm, with an average of 132.5mm. (Conover, 1944; Leukering, 2010; Moskoff, 2011)

Juvenile western solitary sandpipers have an upper dorsal surface that is olive brown in color, with distinctive buff spots. The presence of these buffy spots acts as a distinguishing characteristic in juveniles to differentiate western from eastern solitary sandpipers; however, these spots are only clearly visible through September. Juvenile western solitary sandpipers also have a dusky lower throat, though the color is usually in a longitudinal streak pattern. However, the throat coloration is not present in this way for all individuals and is therefore an unreliable means of distinguishing between juveniles of these subspecies. The outer primary feathers of western solitary sandpipers are typically mottled, many of which are strongly mottled. This mottling pattern acts as a strong distinction between the subspecies, as does the longer wing length of eastern solitary sandpipers. Adult breeding plumage of western solitary sandpipers typically has lighter upper parts that are greyish in color against a dusky olive or brownish plumage. The upper parts of western solitary sandpipers are typically less heavily spotted with white and have more distinct dusky markings on the lower cheeks and throats, the latter of which, however, is not always dependable. This subspecies usually lacks the loral streak from the base of the bill to the eye, and instead has a loral region covered in a fine brownish dusky spotted pattern. A majority of individuals of this subspecies typically have heavy mottling on the outermost primaries with some mottling on the inner webs of these feathers. The p10 shaft color is generally paler in the western variety. The western variety is distinctly larger than the eastern subspecies, with male wing lengths of 128 to 139mm, and an average length of 134.65, and females wing lengths of 137 to 148mm, with an average of 140mm. Distinction between adults subspecies can be performed most readily on unfaded plumage through the lighter, olive coloring of the dorsal surface of the western subspecies, the white mottling of the outermost primary feather, and the larger wing lengths. (Conover, 1944; Leukering, 2010; Moskoff, 2011)

Reproduction

Solitary sandpipers are monogamous and reproduce sexually. Breeding pairs form shortly after arrival on nesting grounds, but little information is known about how mates are chosen. Males perform a courtship display by calling to females while simultaneously rising a few meters into the air and rapidly beating or quivering their wings and spreading their tail so only the outer feathers are in view. Copulation occurs around feeding locations and away from the nesting area in a concentrated period approximately five days prior to the first egg being laid. On mating grounds, males defend a large territory and chase away intruders. In threatening encounters with male conspecifics, males will either attack or retreat. (Moskoff, 2011; Oring, 1973)

Mating pairs of solitary sandpipers frequently use abandoned nests created by other passerine birds and songbirds such as rusty blackbirds and American robins, as well as nests freshly made by other species. Nest elevation varies, but nests are generally found 1.2 to 12m above the ground and up to 200m away from the shoreline, typically in coniferous trees but occasionally in deciduous trees. These nests are discovered by male birds and readjusted by female sandpipers until it is satisfactory. Breeding pairs have only one brood per season, with egg-laying beginning in late May, however, in Ontario, Canada, egg-laying may begin as late as June. Clutches typically consist of 4 eggs, although they can range from 3 to 5 eggs. Eggs are a pale, greenish-white and are heavily blotched and spotted in reddish-brown or purple splotches. The eggs are incubated for 23 to 24 days before hatching. Young solitary sandpipers are precocial and covered in downy feathers; they depart the nest shortly after hatching. (Moskoff, 2011; Oring, 1973)

Male solitary sandpipers help identify the nest that will be used for the breeding pair and the female adjusts the nest to her liking. Solitary sandpipers incubate the eggs within the nest until hatching occurs. Offspring are precocial and are active and downy upon birth. Newborn solitary sandpipers are able to leave the nest shortly after hatching, once their downy feathers dry. Parents are not known to feed their offspring upon hatching. (Moskoff, 2011)

Lifespan/Longevity

There is no available information about the lifespan or survivorship of solitary sandpipers. However, other members of genus Tringa have established lifespans in the wild that range from a maximum of 7.1 to 26.9 years. Wood sandpipers have a fairly similar body size to solitary sandpipers and have a maximum wild lifespan 11.6 years. Other sandpipers with a similar, although somewhat larger body size include marsh sandpipers and green sandpipers, which have lifespans of 7.1 and 11.5 years, respectively. Larger members of the genus, such as common greenshanks and common redshanks have a much longer wild lifespan of 24.4 and 26.9 years, respectively. (Tacutu, et al., 2013)

Behavior

Solitary sandpipers are not gregarious birds and are typically observed alone or in groups of twenty or less. When multiple individuals are together, they typically collectively defend intraspecific territories. While foraging for food on land, solitary sandpipers walk along in shallow water, usually around belly height, while nodding their head. These birds wade slowly within the water, and preen and duck beneath the water while bathing. They also regularly pause to scratch their head with one foot. When startled or flushed into flight, solitary sandpipers exhibit a nearly perfectly vertical ascent. This behavior may be an adaptation for nesting at the edge of wooded areas. General flight patterns are graceful, although alarm responses may include erratic flight reminiscent of a sparrow. When landing, solitary sandpipers hold their wings high above their body and slowly fold them to rest against their body. These birds do not typically fly long distances when disturbed, but rather use flight across a short distance such as the length of a pond when disturbed. (Leukering, 2010; Moskoff, 2011; Oring, 1973)

Home Range

There is no information about the home range of solitary sandpipers. However, during the breeding season, males defend territories against conspecifics. They chase others away or exhibit one of several alarm calls or wing displays; although, solitary sandpipers may build nests as close as 100m from other individuals. In Alberta, Canada, nesting territory size was about 0.5m2. It is unknown if solitary sandpipers are territorial all year, but if they are, territories are probably relatively large. Individuals nest within their territory but do not regularly feed in their defended territory. (Leukering, 2010; Moskoff, 2011; Oring, 1973)

Communication and Perception

Solitary sandpipers frequently use vocalizations as a means of communicating with conspecifics and as warning calls. There are five different call types and two song types created by adult solitary sandpipers, while chicks perform six different calls. Both sexes sing. The songs performed by adults are used in reproduction including mate attraction, territory defense, and maintaining a pair bond. Calls include an alarm-flee call, which signals danger and warns conspecifics, an alarm-attack call to warn conspecifics, signify impending danger, and attract predators, and a contact call, which helps maintain family contact during brooding and hatching periods. Their voice is shriller but more evenly pitched than spotted sandpipers, a similar species. (Moskoff, 2011; "Solitary Sandpiper", 2014; Oring, 1968)

Food Habits

Solitary sandpipers are carnivorous and prey upon a variety of small organisms. The primary food sources for these birds are insects, such as mosquito larvae, young midges, grasshoppers, caterpillars, and beetles, as well as small crustaceans, mollusks, such as snails extracted from their shells, and frogs, primarily as tadpoles. During the winter months, more terrestrial invertebrates are consumed including soil or litter invertebrates, in addition to aquatic invertebrates. Solitary sandpipers typically forage in shallow water that is approximately belly-high, and snatch food out of the water with their beak. Solitary sandpipers will also probe or stir the water and muddy substrate to stir up small creatures from the bottom that they catch and consume while they are fleeing. (Moskoff, 2011)

Predation

Little information is known about the predators of solitary sandpipers; however, peregrine falcons have been known to feed on them in the Alaskan taiga and in Winnipeg, Canada. Gray jays have also been known to take sandpiper eggs from their nests. To avoid predation of their young, solitary sandpipers have been observed feigning being crippled as a means of distraction while juveniles hide in a hole in the ground around the roots of an upturned tree stump. When they are in the water, birds swim or dive to avoid predation. When threatened, this species performs diversionary flight techniques including circles and erratic flight patterns. They also change their body posture or perform vocalizations in response to nearby predators. (Moskoff, 2011)

Ecosystem Roles

Solitary sandpipers consume invertebrates and therefore act as a means for controlling their populations. Additionally, solitary sandpipers act as a food source for their predators and as a host for several species of trematodes and body parasites. (Moskoff, 2011; Tallman, et al., 1985)

Economic Importance for Humans: Positive

Solitary sandpipers consume insects, which may include insects viewed as pests to humans.

Positive Impacts

controls pest population

Economic Importance for Humans: Negative

There are no known negative effects of solitary sandpipers on humans.

Conservation Status

Solitary sandpipers and other shorebirds face habitat loss as natural wetland habitats disappear, particularly in migratory locations. Human disturbance to their habitat puts the species at risk for population decline. Solitary sandpipers are protected under the United States Migratory Bird Treaty Act and migrate throughout the United States. (Conover, 1944; Eldridge, 1992; United States Fish and Wildlife Service, 2013)

Contributors

Yesenia M Werner (author), The College of New Jersey, Matthew Wund (editor), The College of New Jersey, Leila Siciliano Martina (editor), Animal Diversity Web Staff.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

Neotropical

living in the southern part of the New World. In other words, Central and South America.

acoustic

uses sound to communicate

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

freshwater

mainly lives in water that is not salty.

insectivore

An animal that eats mainly insects or spiders.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

male parental care

parental care is carried out by males

marsh

marshes are wetland areas often dominated by grasses and reeds.

migratory

makes seasonal movements between breeding and wintering grounds

molluscivore

eats mollusks, members of Phylum Mollusca

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

taiga

Coniferous or boreal forest, located in a band across northern North America, Europe, and Asia. This terrestrial biome also occurs at high elevations. Long, cold winters and short, wet summers. Few species of trees are present; these are primarily conifers that grow in dense stands with little undergrowth. Some deciduous trees also may be present.

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

Disclaimer:
The Animal Diversity Web is an educational resource written largely by and for college students. ADW doesn't cover all species in the world, nor does it include all the latest scientific information about organisms we describe. Though we edit our accounts for accuracy, we cannot guarantee all information in those accounts. While ADW staff and contributors provide references to books and websites that we believe are reputable, we cannot necessarily endorse the contents of references beyond our control.

This material is based upon work supported by the
National Science Foundation
Grants DRL 0089283, DRL 0628151, DUE 0633095, DRL 0918590, and DUE 1122742. Additional support has come from the Marisla Foundation, UM College of Literature, Science, and the Arts, Museum of Zoology, and Information and Technology Services.